Stop assembly



G. W. HAAB STOP ASSEMBLY April 11, 1961 2 Sheets-Sheet 1 Filed Dec. 1,1959 INVENTOR 501M 02 7. 17m

ATTORNEYS G. W. HAAB STOP ASSEMBLY April 11, 1961 2 Sheets-Sheet 2 FiledDec. 1, 1959 INVENTQR 631M010 iiffi'am BY @400 s W ATTORNEYS UnitedStates Patent STOP ASSEMBLY Gordon W. Haab, 2203 Oakwood Lane, Richmond28, Va.

Filed Dec. 1, 1959, Ser. No. 856,437

6 Claims. (Cl. 198-34) This invention relates to stop mechanisms, andparticularly to stop mechanisms for halting at a predetermined positionarticles advancing along a conveyor, or feed path, and holding thearticle in position until the completion of a specified operation.

Stops of various kinds have been used to control the movements ofarticles along a conveyor path. These have taken the form of hook-likemembers to engage over the edge of the article to be held, pivoted stopplates, pins, etc. All of these require extreme accuracy of location andpreciseness of movement for proper operation. Where a combination ofsuch elements are used, the same problems are present, and springs areusually relied upon as the actuating means to lock the stop in position.

The object of the present invention is to provide an improved stopmechanism which will operate smoothly and positively to accuratelyposition the article to be stopped.

A further object is the provision of a stop assembly which will belatched by positive means and operated by movement of the article to bestopped along its feed path.

Another object is to provide a latch type stop assembly in which thelatch member is a balanced, floating member, positively moved to, andheld in, latching positiom Yet another object is to provide a stopassembly which includes a floating latch member and a stop plate,normally out of engagement, but in which movement of the stop plate in apredetermined direction will cause actuation of the latch to hold theplate against further movement.

A still further object is the provision of such an assembly whereinthere are means to adjust the floating action of the latch member.

Other objects of the invention will become apparent from the followingdescription of one practical embodiment thereof, when taken inconjunction with the drawings which accompany, and form part of, thisspecification.

In the drawings:

Figure l is a vertical section through a stop assembly embodying theprinciples of the present invention, with the stop assembly being shownin association with a case conveyor with a case moving into position tobe stopped, and with the case and stop assembly being shown in dottedlines in the positions occupied when the case is held in stoppedposition;

Figure 2 is a vertical transverse section through the stop assemblyhousing, taken on the line 22 of Figure 1;

Figure 3 is another vertical transverse section taken in the plane ofthe latch pivot and substantially on the line 3-3 of Figure 1; and

Figure 4 is a perspective view of the latch arm with the parts shownseparated from one another for clarity.

In general, the invention concerns a stop assembly for articles, such asbottle, or carton, cases, moving along a conveyor line to stopsuccessive articles,.or cases, and hold them in predetermined positionon the line. The stop assembly includes a stop plate to be contacted bythe cases, and a latch operable when the plate is contacted to latch theplate against movement to hold a case in position. The latch is solenoidoperated to latched-position, and has a counterbalanced, free floatingmovement when released.

Referring to the drawings in detail, there is shown a stop assembly Imounted above a case-feeding conveyor 2 on which a case 3 is being fedto a predetermined position where it will be stopped and held forloading or other operation. The case and its conveyor are merelyillustrative of any article which is to be stopped and held, and itsconveying means.

The stop assembly is mounted in a housing 4 upon a suitable frame 5. Theframe may consist of front and back plates 6 and 7, longitudinal struts8 and 9, a transverse brace 10, and vertical struts 11 and 12, extendingfrom the transverse brace to the longitudinal. This frame may bemodified as needed, and is merely illustrative of a suitable frame forsupporting the operating members of the device. 9

The transverse brace 10 carries two brackets 13 near its ends, betweenwhich a stop plate 14 is pivoted. The plate is of rectangular shape andhas a pivot pin 15 extending across its back with its ends journaled inthe brackets 13. The plate may have free swinging movement about itspivot, but is biased toward an angular position wherein its lower end isadvanced toward the direction from which cases will move to the stop. Itis yieldingly held in this position by means of a spring 16 connected tothe plate near its top end to the longitudinal strut 8. Upon contact ofa case with the lower end of the plate, the plate may swing in aclockwise direction as viewed in Figure 1 against the action of spring16.

A latch 17 is pivotally mounted upon a pivot pin 18 fixed in thevertical struts 11 and 12. The latch consists are provided with latchingnotches 25 and 26.

At the back end of the latch body 19 there is a support post 27 havingits opposite ends threaded and screwed into the latch body and acounter-weight 28. Lock nuts 29 hold secure the post to those elementsand permit adjustment to vary the distance of the counterweight from thebody. This, of course, will vary the effective weight of thecounter-weight upon' the latch member. The latch trigger has adown-turned arm 30 at its rear in contact with a switch arm 31 of amicroswitch 32 mounted beneath the counter-weight. It m'll be seen thatadjustment of the counter-weight toward and from the latch body willalso serve to determine the position of the micro-switch arm and therelative posi-' tions of the latch body and trigger when contact betweenthe trigger and switch arm is made and broken. A spring 33 connected topins on the trigger and counterweight serves to bias the triggerrearwardly against the arm of the micro-switch. This will serve to holdthe switch in open position. When the parts are in this position, thetrigger is retracted and their respective 1 notches are in steppedrelation, with the notch of the trigger rearwardly disposed relative tothat of the latch body.

The support post 27 has one end of a coil spring 34 connected to it, andthe other end of the spring is connected to the movable core member 35of a solenoid 36.

This serves to yieldingly, or floatingly, suspend the rear portion ofthe latch against the Weight of the counterbalance 28. It will be seenthat by adjusting the counterweight position, more or less weight willbe imposed upon the spring 34, and the angular position of repose of thelatch may be closely adjusted. When in this position, only slightpressure is required to swing the latch on its pivot 18 in eitherdirection. It will be understood that micro-switch 32 and solenoid 36are in circuit with a source of power and that when the switch closesthe solenoid will be energized and lift the back end of the latch toswing the latch about its pivot to assume a horizontal position, asshown in dotted lines in Figure 1.

Referring particularly to Figure 1, it will be seen that the upper endof stop plate 14 rests in the notch 25 of the latch body, held againstthe back edge of the notch by spring 16. At the angle which the latchassumes, the stop plate would move out of the notch when swung about itspivot. The retracted trigger, however, effects a reduction of the notchopening, and the stop plate will not clear the trigger notch but willcontact'it. Thus, if a casing moving along the conveyor 2 strikes thelower end of the stop plate it will rock the plate in a clockwisedirection about its pivot causing the upper end of the stop plate tomove forward and contact the trigger notch. Continued movement of theplate will move the trigger forward relative to the latch body, thusmoving the arm 30 from the switch arm 31 and allowing switch 32 toclose, energizing the solenoid. The solenoid will lift its core andswing the latch to a substantially horizontal position, positivelylocking the stop plate against further movement when it strikes the edgeof the latch body notch and definitely holding the case in position.When the case is filled, or other operation performed, the solenoidcircuit will be broken by other means not shown. The weighted latch willswing immediately about its pivot, lifting its notched end free of thestop plate and permitting the plate to rotate and allow the case to movefreely on the conveyor. When the case has passed, the stop plate willswing back about its pivot under the influence of spring 16. By thistime, spring 33 will have retracted the trigger to its originalposition. This will place at least the trigger portion of the latch inthe path of swinging movement of the stop plate, but the plate willstrike the cammed edges of the latch or trigger and the latch will liftto allow the top of the stop plate to drop into the notch. Spring 34will give freely to allow this movement. The assembly is now ready tooperate upon the movement of another case along the conveyor toward thestop position.

While in the above one practical embodiment of the invention has beendisclosed, it will be understood that the details of construction shownand described are merely by way of example, and the invention may takeother forms within the scope of the appended claims.

What is claimed is:

1. A stop assembly for positioning an article moving along a conveyorcomprising, a frame, a stop plate pivotally mounted intermediate itsends and the frame adapted to be positioned to have one end in the pathof movement of articles along the conveyor, a latch pivotally mounted onthe frame, said latch including a latch body and a latch triggerslidably mounted on the latch body, the latch body and latch triggerhaving companion notches for engagement over the end of the stop plate,the effective span of the combined notch being determined by theposition of the latch trigger relative to the latch body, means toretract the latch trigger to reduce the effective span of the notch, amicro-switch carried by the latch body and actuated by contact of thelatch trigger when in retracted position, a solenoid connected to thelatch to swing the latch to locking engagement with the stop plateactuated by the micro-switch when contact between the microswitch andlatch trigger is broken by forward sliding movement of the latchtrigger, said trigger when in retracted position having its notchengageable with the stop plate for forward movement by the stop platewhen the stop plate is rocked about its pivot.

2. A stop assembly as claimed in claim 1 wherein the latch has acounterbalance positioned to normally swing the latch to stop platereleasing position.

3. A stop assembly as claimed in claim 2 wherein the counterbalance ismovable relative to the latch body to adjust the weight distribution ofthe latch.

4. A stop assembly as claimed in claim 1 wherein the connection betweenthe solenoid and latch is a yieldingly extensible one.

5. A stop assembly as claimed in claim 1 wherein the stop plate isbiased to urge said one end in a direction contra to that of movement ofarticles on the conveyor.

6. A stop assembly for positioning an article moving along a conveyorcomprising, a frame, a stop plate pivotally mounted on the frame toprovide an article-engaging end and a latch-engaging end, a latchpivoted to the frame and having a notch to seat over the latch-engagingend of the stop plate when the latch is moved to plate-engagingposition, said latch being biased away from plate-engaging position, alatch trigger slidably mounted in the latch and having a notch to engagethe latch-engaging end of the stop plate, means to bias the latchtrigger to stop plate engaging position, means to move the latch toengage the stop plate, means to actuate the latch moving means normallyheld in inactive position by engagement with the latch trigger in biasedposition, and means to bias the stop plate latch-engaging end in thesame direction as the latch trigger is biased, whereby upon movement ofthe stop plate in an opposite direction by contact of the article movingalong the conveyor the stop plate will move the trigger from engagementwith the latch moving actuating means to actuate the latch to engage thestop plate.

References Cited in the file of this patent UNITED STATES PATENTS2,921,665 Whitecar Jan. 19, 1960

